1. Field of the Invention
The present invention relates to a liquid drawing device, especially to a drawing device which draws liquid by a pump and can adjust air concentration of the liquid.
2. Description of the Prior Arts
A liquid drawing device is a device for drawing a beverage in a container, and is capable of mixing the environmental air into the beverage during the drawing. A common process is applied to wine, mixing air to the wine for decanting during the drawing of the wine. When applied to drawing mineral water, the liquid drawing device can increase an oxygen content of the mineral water drawn from the bottle. Thus, the liquid drawing device can improve the flavor of the beverage.
A conventional liquid drawing device, as disclosed in Taiwan Patent NO. 1339704, compresses the environmental air into a container by operating an air pump, and the compressed air presses a surface of liquid inside the container, which has an opening maintained at a good airtight condition, so that the liquid is pressed into an insert pipe of the casing and then is guided to an outlet pipe and flows out of the container. Meanwhile, during the procedure of the liquid flowing through the insert pipe, another compressed air is mixed with the flowing liquid via a vent of the insert pipe and thereby the purpose of decanting is achieved.
However, the airtight condition between a compressing device and an opening of the container should be well maintained during an operating process of the conventional liquid drawing device, or an efficacy of transporting environmental air into the container and compressing the air will be decreased because the airtight condition is not maintained well. Besides, a vent of the conventional liquid drawing device has regular dimensions so that the user can control the size of the vent according to a type of the beverage. For instance, when the drawn beverage is white wine, which does not have to undergo a decanting step, the vent should be closed. In addition, a drawing straw is a regular-length pipe. Because the drawing straw cannot be shortened, the user will encounter problems when carrying the whole liquid drawing device.